Tool reciprocator



Sept. 19, 1933 5 E v 1,927,793

TOOL REC I PROCATOR Filed Aug. 10, 1929 3 Sheets-Sheet l I N V EN TOR.

ATTORNEY.

Sept. 19, 1933. DE V 1,927,793

TOOL REC I PROCATOR Filed Aug. 10, 1929 3 Sheets-Sheet 2 ATTORNEY.

Sept. 19, 1933. A 5 VERE 1,927,793

TOOL RECIPROCATOR Filed Aug. 10, 1929 3 Sheets-Sheet 3 IN VEN TOR.

A TTORNEY Patented Sept. 19, 1933 UNITED STATES V roonneolrnocuoa Andrew De Vere, Pontiac, Mich., assignor to The Willis Overland Comp poration of Ohio any, Toledo, Ohio, a cor- Application August 10, 1929; SerialNoJ 384,932

3 Claims. (Cl. 5134) This invention relates to tool reciprocating devices and more particularly to means for axially reciprocating agrinding wheel.

In grinding operations it is preferable to re- 5 ciprocate the grinding wheel with respect to the work. This is especially true in grinding cylindrical articles provided with surface grooves or slots, such as the sleeves of a sleeve valve engine, in order to avoid the formation of ridges on the wheel, with consequent inaccuracies in the finished surface. With this type of work, it isalso necessary that the reciprocating movement be greater than the width of any grooves in the surface, and that the movement be smooth and constant, without an appreciable stop at the point of reversal.

Accordingly, the principal object of this invention is to provide an improved means for reciprocating a grinding wheel or other tool to secure the most desirable movement.

A further object is to construct the reciprocating device in such a manner'that any desired length of stroke or rate of reciprocation can be selected for a particular rate of rotation.

A further object is to utilize an eccentric or crank and connecting rod to produce the reciprocating movement, whereby a smooth, positive reciprocation is obtained with a minimum of stoppage and frictional loss.

These, together with other objects relating to economies and advantages of construction, will become more apparent upon consideration of the particular embodiments of the invention selected for illustration herein.

In the accompanying drawings Figure I is a schematic plan view of a centerless grinder with the preferred form of the improved reciprocating device attached to one end of the grinding wheel shaft;

Figure II is an enlarged section on the line II--II of Figure I;

Fig. III is a section on the Figure II;

Fig. IV is a plan view of the device shown in Figs. I, II, and III with the cover plate removed;

Fig. V is a plan view of the eccentric shaft; and

Fig. V1 is a sectional view of a modification.

Referring to Figures I to V of the drawings, the numeral 1 represents a conventional centerless grinder having a grinding wheel 2, mounted on a shaft or spindle 3 driven by any suitable means, such as a belt (not shown). A casing 4 is mounted on the frame of the grinder in line with the end of the shaft 3. The shaft 3 is extended into the casing and has a worm gear 5 line IIIIII of of the shaft 3.

keyed thereon. A pair of, supportingrods 6, 6, are mounted on the rear wall of the casing and project outwardly therefrom parallel with the shaft 3, and a frame or cage structure 7 is slidably mounted upon the'rods 6, 6. p I

The upper cross piece-8 of the frame '7- is provided with a bearing for the shaft Thrust washers 9 are interposed between the worm gear 5 and the cross piece 8, and between the cross piece and the nut 10, which is secured to theend 1.65

An eccentric shaft 11 is journalled in. the frame 7 below and atright angles to shaft 3. Connecting rods 12 are pivoted to the eccentric portions of the shaft 11 and to red-13 which is fixed inany suitable manner to the rear wall of the casing 4. A worm'wheell4 is rotatably mounted upon the eccentric shaft-1=1 in mesh with the worm; ear 5. f I

7 One side .of the worm wheel 151$ providedwith a conical depression 15 for co-operation with a clutch 16. The clutch 16 is secured to shaft 11 by' means of a key 1'7, which passes through the clutch and through a slot 18 in shaft 11. Shaft 11 is provided with an axial bore 19 extending from one end of the shaft past the slot 18. A spring 20 located in the inner end of the bore 19 bears against the pin 17 and presses the clutch 16 outwardly to a released position. The outer end of the bore 19 is tapped for co-operation with the threads of a rod 21 which extends inwardly and engages the outer side of the. pin 17. The rod 21 passes through an aperture 22 in the casing 4; and terminates in the hand wheel 23. A flexible washer 24 is disposed about the rod 21 and in the aperture 22 to seal the casing but to permit lateral movement of the rod.

When the grinding wheel is rotated the worm gear 5 drives the worm wheel 14. When the rod 21 has been screwed inwardly to force the clutch 16 into engagement with the conical surface v15 of the worm wheel, the eccentric shaft rotates with the worm wheel 14. The eccentric portions of the shaft 11 impart motion to the connectingrods 12 which has vertical and horizontal components. The vertical components cause the rods 12 to oscillate about their pivots on the fixed rod 13. The horizontal components force the shaft 11 and the frame '7 to slide horizontally on the supporting rod 6. This motion is transmitted by the upper cross piece 8 of the frame 7 through the thrust washers 9 to the shaft 3.

When it is desired to dress the grinding wheel, orto allow the shaft 3 to rotate without reciproeating, for any other reason, the rod 21 is screwed outwardly to allow the spring 20 to force the clutch.

16 out of engagement with the surface 15.

In the modified form of the device shown in Fig. VI, the frame is omitted. The-eccentric shaft 11 is journalled at the ends in the casing 4. A collar 25 is rotatably mounted on the shaft 3 and bears through thrust washers 9 on the worm gear 5, and through a thrust ball bearing 26 on the nut 10 which is fixed to the end of the shaft. The connecting rods 12 are pivoted to the eccentric portions of the shaft 11 and to studs 27 projecting from opposite sides of the collar 25. I

In the operation of this form of the device, rotation of the eccentric shaft'imparts a reciprocating motion directly to the shaft 3 through the connecting rods, the collar 25, and the thrust bearings. It will be apparent that sincethe worm,

gear 5 isfixed to the shaft 3, the reciprocation of the latter creates an irregularity in the rate of rotation of the wheel 14, and a corresponding irregularity in the rate of reciprocation.

As the eccentric shaft is substantially offset from the axis of theshaft 3, the varying rate of action is substantially the same in both directions and has proven very satisfactory.

While I have described in detail-two embodiments of the invention, it will be apparent that other modifications can bemade, and I do not,

rod pivoted to said eccentric and to said support,

whereby rotation'of said shaft imparts a reciprocating movement to said cage and said primary shaft. I

2. In combination, a stationary casing; a rotatable drive shaft journalled in said casing; projections on said casing, a cage slidably mounted upon said projections; an operative connection between said cage and said shaft; means within said. casing actuated by rotation of said shaft for reciprocating the shaft and cage axially; and means operable from outside said casing for rendering said first mentioned means operative or inoperative at will.

3. In combination'with a tool spindle a mov- 100 able cage'having a portionconnected to said spindle; means independent of said spindle for supporting said cage; a shaft journalled on said cage positioned at an angle to said spindle; gearing interposed between said shaft and spindle 1G5 whereby rotary movement of said spindle causes rotation of said shaft, said shaft having an cecentric; a relatively stationary member spaced from said eccentric; and a connectingrod pivoted to said eccentric and to said stationary' member whereby rotation of said shaft imparts movement to said cage for reciprocatingsaid spindle. I

' ANDREW-DE vERE."

CERTIFICATE OF CORRECTION.

Patent No. 1,927,793. September 19, 1933.

ANDREW De VERE.

It is hereby certified that the name of the assignee in the above numbered patent was erroneously written and printed as "The Willis -Overland Company" whereas said name should have been written and printed as The Wiliys Overland Company as shown by the records of the case in this office; and that the said Letters Patent should be read with this correction therein that the same may conform to the recor of the case in the Patent Office.

Sign d and sealed this 5th day of December, A. D. I933,

F. M. Hopkins (Seal) Acting Commissioner of Patents. 

